Easily Replaceable Valve Assembly for a High Pressure Pump

ABSTRACT

A valve assembly for use in high pressure pumps is designed for easy replacement for example in the suction inlet here for a high pressure pump. The design utilizes a combination of screw threads and a locking member to provide structural strength for the valve to be placed in and withdrawn from the inlet bore.

BACKGROUND OF INVENTION

1. Field of the Invention

This invention relates to high pressure fluid pumps and in particular toan arrangement for allowing easy access to and repair/replacement ofsuction valves located within the pump housing.

2. Description of Related Art

High pressure reciprocating piston pumps have been used in the oilindustry for several purposes such as hydraulic fracturing, cementing,and other well treating processes. Typical pump assemblies are disclosedin U.S. Pat. No. 6,544,012 issued to Blaine. The pumps generally includea power end and a fluid end. The power end includes a power source andlinkage for reciprocating a plurality of plungers within the fluid endof the pump. The fluid end includes a suction manifold, a plurality ofintake or suction valves, a plurality of output valves and a dischargeheader. The fluid pressure within the pump chamber can be in excess offifteen thousand psi and the fluid being pumped often contains abrasivematerials such as sand. Consequently the valves are subject to extremeconditions which cause failures and require regular service andreplacement. It is therefore desirable to construct the valve assemblyso as to be easily accessible and replaceable in a short period of time.

Current methods for accessing the suction valves include providing abore with a plug as shown in U.S. Pat. No. 7,681,589 at 38 and 40 inFIG. 1. Another method is disclosed by Blume in the above mentioned U.S.Pat. No. 6,544,012 that includes providing a threaded suction valve seatretainer 135. However in high pressure applications the threads on thevalve seat retainer are not sufficient to withstand the force within thepump chamber.

BRIEF SUMMARY OF THE INVENTION

The present invention overcomes the above mentioned deficiencies in theprior art by providing a suction valve assembly that is modular innature and is secured in place by using a dual locking arrangement whichdistributes forces delivered by the pumping system between a threadedvalve seat collar and a locking ring which includes a plurality ofaccurate segments. The invention may be applied to a stem guided valvetype suction valve or to a “crows feet” guide suction valve.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

FIG. 1 is a perspective view of the fluid end of a typical high pressurepump.

FIG. 2 is a cross sectional view taken along line 2 of FIG. 1.

FIG. 3 is a cross sectional view of a valve according to an embodimentof the invention.

FIG. 4 is a perspective view of the valve seat and stem guide shown inFIG. 3.

FIG. 5 is a perspective view of one of the segments of the locking ring.

FIG. 6 is a cross sectional view of a flow diverter for the valveaccording to the invention.

FIG. 7 is a cross sectional view of a “crows feet” valve assemblyaccording to a second embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 illustrates a conventional fluid end 10 of a high pressure pump.The fluid end includes an inclined top surface 20 having a plurality ofbores 12 for receiving outlet valve mechanisms which are not shown.Fluid end 10 has a planar front side 11 and a rear side 13 that isadapted to be bolted to the power end. Suitable bores 14, 15 areprovided for receiving threaded studs with nuts. A horizontallyextending outlet passageway 16 is in fluid communication with each ofthe outlet chambers 21 of the pump as shown in FIG. 2. Fluid end 10further includes a lower extending inclined portion 19. A plurality ofinlet ports 22 are located in portion 19. Planar front side portion 11externals vertically between inclined surfaces 20 and 19 when the pumpis secured to a truck bed. The rear side 13 of the fluid end includes aplurality of bores 23 for receiving the pistons (not shown) which aredriven by the power end of the pump. The arrangement of the pistons, thefluid inlet, and the fluid outlet is commonly referred to as the “Y”design for a frac pump as shown in FIG. 2. However, a “T” configurationas known in the art could also be used.

FIG. 2 illustrates the interior details of a typical pump chamberincluding suction inlets 22, outlet chamber 21 and outlet passageway 16.Suction valves (not shown) are located within bores 22 and outlet valvesnot shown) are located in bores 12. A plurality of bores 23 are adaptedto receive the pump plungers which are driven by the power end of thepump.

A valve assembly according to an embodiment of the invention isillustrated in FIG. 3. Valve assembly 51 includes a threaded valve seatcollar 50, a locking ring 34 which includes a plurality of lockingelements 74, valve stem 39 which includes a valve insert member 45 and aspring retaining member 36.

Valve seat collar 50 is threaded at 52 so as to be threadly received ininlet bore 33 of fluid end 31. Valve seat collar 50 includes a valvestem guiding member 35 which is supported by arms 47 that extend betweenthe inner portion of the valve seat collar and valve stem guiding member35, see FIG. 4. Valve seat collar 50 also includes a shoulder 48 and anannular ridge 32 that cooperates with the locking elements 74 to helpsecure the valve seat collar within the bore in a manner to be discussedbelow. A spring 37 which may be a coil spring is disposed between ashoulder 46 on the valve stem guide 35 and a shoulder 38 provided onspring retaining member 36. A locking pin not shown holds springretaining member 36 on valve stem 39. Member 36 could also be threadedor welded to valve member 39. The spring is biased to urge upper portion44 with insert member 45 into engagement with valve seat 41 provided onthe valve seat collar 50.

Locking elements 74 are shown in FIG. 5 and include an arcuate,generally rectangular shaped body 71. At its outer surface the edges ofthe top and bottom portions are beveled at 72, 73 to allow the segmentsto more easily be located within groove 40 in the bore 33 of the fluidend. A flow diverter 80 as shown in FIGS. 6 and 6 a is positioned withinthe bore 33 at its opening.

A U-shaped seal 120 which includes an O-ring 121 positioned within theU-shaped channel is positioned between valve seat collar 50 and a recessin the inlet bore as shown in FIG. 3. These seals are available fromMarco Rubber & Plastic Products, Inc., among others.

The manner of installing the valve assembly into the fluid end is asfollows. Initially locking elements 74 are not placed within the suctioninlet bore. The valve assembly including valve seat collar 50, valvestem 39 with spring 37 and spring retainer 36 are threaded into bore 33using a suitable tool that has complimentary ridges that align withgrooves 61 provided on the valve seat collar. The assembly is threadedinto the bore to a point where the end shoulder 48 of valve seat collar50 passes the inner top portion of groove 40. A plurality of lockingsegments for example four are now positioned in the groove 40. [Valveseat collar 50 is backed out of the bore 33 to seat against the lockingelements 74.] In this position the high pressure within the chamberduring compression is withstood by both the threads 52 on the valve sealcollar and the locking elements 74 within annular groove 40. The flowdiverter 80 as shown in FIG. 6A is then placed within the inlet bore 33and held in place by a suction manifold plate 101 attached to fluid end31 by any suitable means such as a bold and nut. Annular ridge 82 of theflow diverter keeps locking elements 74 within groove 40.

To remove and repair or replace the suction valve assembly, the manifoldcover plate 101 and flow diverter 80 are removed from the suctionmanifold. The valve removal tool is inserted into the valve seat collarto slightly screw member 50 into the valve inlet bore. At this pointlocking elements 74 may be removed from groove 40 and are withdrawn.Valve assembly 51 can now be entirely removed by screwing valve seatcollar 50 out of bore 33. A new or refurbished valve assembly can now beinstalled as described above.

A second embodiment of the invention is illustrated in FIG. 7 whereinlike components have the same reference member as the embodimentillustrated in FIGS. 3-6. Fluid end 31 includes inlet bore 95 having arecessed groove 40. Valve seat collar 51 in this embodiment includes afirst portion 69, a second portion 90, and a third portion 107. A valvemember 85 has a lower portion 87 which cooperates with a frusto-conicalvalve seat surface 103 on an interior surface of valve seat collar 51.

A spring guide and support member 92 is threaded at 140 into upperportion 107 of the valve seat collar 51. A spring 93 is supportedbetween spring, guide 88 and a shoulder 84 provided on the valve element85 as shown in FIG. 7.

Valve seat collar 51 is externally threaded at 111 and cooperates withinternal threads 94 provided in bore 95. An O-ring 122 is capturedwithin a groove 123 in inlet bore 95 and abuts against a beveled endportion 141 of valve seat collar 51.

To position the valve assembly within intake bore 95, spring guide andsupport member 92 is threaded into valve seat collar 51. Spring 93,valve member 85, and valve seat collar 51 are then placed within thebore and valve seat collar 51 is threaded into the bore 95 to a positionwhere portion 90 clears groove 40. These elements may be formed as asingle cartridge unit that is preassembled. Next locking elements 74 arepositioned within the groove 40 as shown in FIG. 7 to further supportthe valve assembly within the bore. After the locking elements areplaced within groove 40, the flow diverter and locking ring retainer 80is positioned within bore 95 such that annular ridge 82 of the retaineris located between locking segments 74 and lower portion 69 of the valveseat collar. Valve seat collar Si is backed out of the bore 33 to seatagainst the locking elements 74. This arrangement prevents the lockingsegments from moving out of groove 40. Retainer 80 is held in positionby a suction manifold plate 101 that is bolted or otherwise secured tofluid end 31. Removal can be accomplished simply by reversing theinstallation process beginning by removing the suction plate, retainer80 and locking segments 74. The remaining valve assembly may they beremoved as a unit out of inlet bore 95.

Although the present invention has been described with respect tospecific details, it is not intended that such details should beregarded as limitations on the scope of the invention, except to theextent that they are included in the accompanying claims.

1. A valve assembly for a fluid end of a high pressure pump, the fluidend including at least one suction inlet in which the valve is adaptedto be placed comprising: a threaded valve seat collar having a valveseat, a valve member extending within the threaded valve seat collar forreciprocal movement, the valve member having a valve surface forengagement with the valve seat; and a locking ring adapted to bepositioned in a groove provided in the suction inlet to support thevalve assembly within the suction inlet.
 2. A valve assembly accordingto claim 1 wherein the locking ring comprises a plurality of arcuatemembers.
 3. A valve assembly according to claim 1 further including aflow diverter.
 4. A valve assembly according to claim 1 wherein thethreaded valve seat collar includes a valve stem guide having a shouldertherein and a spring retaining member secured to the valve member havinga shoulder therein; and a spring extending between the shoulder on thespring retaining member and the shoulder on the valve stem guide.
 5. Avalve assembly according to claim 1 and further comprising a springguide and support member.
 6. A valve assembly according to claim 5further comprising a spring positioned between the spring guide andsupport member and the valve member.
 7. A valve assembly according toclaim 2 wherein the locking accurate members have edges that are beveledto facilitate movement of the members into the groove provided in thesuction inlet.
 8. A fluid end for a high pressure pump comprising: abody member have at least one plunger bore, at least one suction inletbore and at least on outlet bore, the inlet bore having a threadedportion and a groove, a threaded valve seat collar having a valve seatand threadly engaged with the threads provided in the inlet bore, avalve member extending within the thread valve seat collar forreciprocal movement; and the valve member having a valve surface forengagement with the valve seat, and a locking ring positioned in thegroove in the inlet bore and engaging a shoulder portion on the threadedvalve seat collar to support the valve assembly within the inlet bore.9. A fluid end for a high pressure pump according to claim wherein thelocking ring comprises a plurality of locking members.
 10. A fluid endfor a high pressure pump as claimed in claim 8 further including a flowdiverter located within the inlet bore upstream of the threaded valveseat collar.
 11. A fluid end for a high pressure pump according to claim8 wherein the threaded valve seat collar includes a valve stem guidehaving a shoulder therein, and a spring retaining member secured to thevalve member having a shoulder therein; and a spring extending betweenthe shoulder on the spring retaining member and the shoulder on thevalve stem guide.
 12. A fluid end for a high pressure pump according toclaim 8 and further comprising a sprint guide and support member.
 13. Afluid end for a high pressure pump according to claim 12 and furthercomprising a spring positioned between the spring guide and supportmember and the valve member.
 14. A fluid end for a high pressure pumpaccording to claim 9 wherein the locking members have edges that arebeveled to facilitate movement of the members into the groove providedin the inlet.
 15. A method of servicing a valve in the suction inletbores of a fluid end of a high pressure pump comprising: removing thesuction inlet valves from the suction inlet bores, providing threads anda groove on an interior portion of the suction inlet bore, threading anew or refurbished valve assembly into the threaded portion of thesuction inlet bore; and inserting a locking ring into the groove tomaintain and support the valve assemblies within the suction inletbores.